HHS wrote:FlugHund,
SAS- that dampes the rate of the movements of the heli. Means- the heli gets more sluggish, which makes it a bot more stable.
On all middle and big helis is this a standard feature!
You can see how SAS works by engaging/disengaging SAS while applying "full roll." you'll see engaging SAS restricts the roll rate.
CAS adjusts the pilot's input so heli's maneuver goes close to pilot's expectation. There're lots of factors that affects roll/pitch/yaw rates so a certain stick movement will output different rates depending on a situation. CAS is for eliminating such factors and gives a constant maneuver for the same input. There are some ways to implement CAS, including attitude control, rate control, and air speed control. OH-1 has attitude control and rate control, and you can switch these.
You can see how CAS (attitude command) works by keeping the stick to the same position, and heli (say OH-1) will keep its bank/pitch angle as long as possible.
Some helis have combined CAS and SAS (called SCAS), and others have separated SAS and CAS. OH-1 has SCAS for primary FCS, and SAS for backup FCS.
Tat